Weight adjustable golf club head

ABSTRACT

The club head contains a number of blind holes arranged at appropriate places other than the hitting surface of the club head. Each blind hole is for the accommodation of a weight member. Each weight member contains at least a weight element and a fastening element. The fastening element has a threaded rod extending from the bottom of a cone-shaped head. The fastening element is squeezed into an end of the weight element with the threaded rod penetrating through the weight element and into the club head for fixation. On the other hand, the circumference of the weight element has a number of slits so that the cone-shaped head of the fastening element can force the wall of the weight element to press tightly against the hole to further enhance the fixation.

(A) TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to a golf club head, and moreparticularly to a golf club head whose center of gravity is adjustable.

(B) DESCRIPTION OF THE PRIOR ART

In recent years, as the manufacturing technologies for golf club headscontinuously advance, large varieties of club heads of various forms andspecifications are developed. The main purpose of all these new clubhead designs is nothing but to help golfers to hit the balls farther andmore accurately. However, a golfer's performance still has a very largepart related to the golfer's stance and habit.

Therefore, so-called “weight tunable club heads” are developed andclaimed to be able to adjust the club head's center of gravity to bestsuit a golfer's stance and habit. These “weight tunable club heads”generally have a number of fixed positions arranged on the club head andweights in the form of bolts are inserted or taken out so as to adjustthe club head's center of gravity. There are also some “weight tunableclub heads” allowing different weights to be placed in fixed positionsof the club head. However, these approaches require that the club headsto be formed in high precision and the formation of the bolt holes isquite demanding in terms of both production time and effort. Any slightdeviation in the manufacturing process will render the club headuseless, thereby significantly increasing the resource consumption andproduction cost. It is because of these manufacturing issues that“weight tunable club heads” usually have hefty price tags. Moreover, toachieve bolts of different weights, the bolts have to be made of anappropriate material and the limited material selection also affectswhere these bolts can be placed on the club heads. Therefore, it is verydifficult to have a single design to meet the needs of golfers ofvarious skill levels.

SUMMARY OF THE INVENTION

A novel club head is provided herein. The club head contains a number ofblind holes arranged at appropriate places other than the hittingsurface of the club head. Each blind hole is for the accommodation of aweight member. By altering the weight of the weight members or theirlocations in the blind holes, the center of gravity of the club head isadjusted.

Each weight member contains at least a weight element and a fasteningelement. The fastening element has a threaded rod extending from thebottom of a cone-shaped head. The fastening element is squeezed into anend of the weight element with the threaded rod penetrating through theweight element and into the club head for fixation. On the other hand,the circumference of the weight element has a number of slits so thatthe cone-shaped head of the fastening element can force the wall of theweight element to press tightly against the hole to further enhance thefixation.

The foregoing objectives and summary provide only a brief introductionto the present invention. To fully appreciate these and other objects ofthe present invention as well as the invention itself, all of which willbecome apparent to those skilled in the art, the following detaileddescription of the invention and the claims should be read inconjunction with the accompanying drawings. Throughout the specificationand drawings identical reference numerals refer to identical or similarparts.

Many other advantages and features of the present invention will becomemanifest to those versed in the art upon making reference to thedetailed description and the accompanying sheets of drawings in which apreferred structural embodiment incorporating the principles of thepresent invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded diagram showing the various componentsof a club head according to a first embodiment of the present invention.

FIG. 2 is a perspective diagram showing the club head of FIG. 1 afterits assembly.

FIG. 3 is a sectional diagram of the weight member of FIG. 1 when thefastening element is not tightly screwed into the weight element.

FIG. 4 is a sectional diagram of the weight member of FIG. 1 when thefastening element is tightly screwed into the weight element.

FIG. 5 is a sectional diagram along the X-X line of FIG. 4.

FIG. 6 is a sectional diagram showing the weight member according to asecond embodiment of the present invention.

FIG. 7 is a sectional diagram showing the weight member according to athird embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are notintended to limit the scope, applicability or configuration of theinvention in any way. Rather, the following description provides aconvenient illustration for implementing exemplary embodiments of theinvention. Various changes to the described embodiments may be made inthe function and arrangement of the elements described without departingfrom the scope of the invention as set forth in the appended claims.

As shown in FIGS. 1 and 2, a club head 1 according to a first embodimentof the present invention has a number of cylindrical blind holes 11 ofappropriate depths into the interior of the club head 1 configured onthe back surface (i.e., the curved surface opposite to the hittingsurface of the club head 1) with appropriate spacing among them. Each ofthe blind holes 11 therefore provides a storage space 12 for theaccommodation of a weight member 2.

The weight member 2 contains a tubular weight element 23, and afastening element 22 and a seat element 21 plugged into the two ends ofthe weight element 23, respectively. The diameter of the weight element23 is slightly smaller than the aperture of the blind hole 11 so thatthe weight element 23 can be slid into the blind hole 11. Along thecircumference of the weight element 23, a member of through slits 231are provided along the axial direction from a first end towards theother, second end (but not reaching the second end). Similarly, a numberof through slits 232 are provided along the axial direction from thesecond end towards the first end. The slits 231 and 232 are interleavedand uniformly spaced so that the two ends of the weight element 23 aresomewhat flexible to expand and recover radially.

As shown in FIG. 3, the seat element 21 has a cone-shaped body with acircular base 211 having a slightly larger diameter than that of thebody and an axial threaded through channel 213. On the other hand, thefastening element 22 has a cone-shaped head and a threaded rod 221extending axially from the bottom of the cone-shaped head. Please notethat the wall of weight element 23 actually grow thinner from the middlesection towards the ends and, as such, when the fastening element 22 andthe seat element 21 are plugged into the two ends of the weight element23, respectively, the cone-shaped head of the fastening element 22 andthe cone-shaped body of the seat element 21 are well received by thewall of the weight element 23, as shown in FIG. 3. Then, by rotating thefastening element 21 through a slot or hole 222 on the top surface ofthe head, the threaded rod 221 is screwed into the through channel 213so that the three elements 21, 22, and 23 are joined together into theweight member 2. The diameters of the elements are configured such thatthe weight member 2 is perfectly accommodated by the blind hole 11 onthe club head 1.

As shown in FIGS. 1 and 3, the bottom of each blind hole 11 has asmaller hole 121 in the center that is aligned with the through channel213 of the seat element 21 when the weight member 2 is placed inside theblind hole 11. Further, as shown in FIGS. 4 and 5, the threaded rod 211can be screwed all the way through the through channel 213 of the seatelement 21, and hole 121 of the blind hole 11, and into the interior ofthe club head 1. As such, together with the two ends of the weightelement 23 being expanded to press tightly against the wall of the blindhole 11, the weight member 2 is fixedly locked to the club head 1 toaffect or adjust the center of gravity of the club head 1.Correspondingly, when the fastening element 22 is unscrewed and as thethreaded rod 221 is removed from the hole 121 and the through channel213, the pressure against the wall of the blind hole 11 is released andthe weight member 2 can be conveniently taken out of the blind hole 11.

When screwing or unscrewing the fastening element 22, to prevent theseat element 21 to rotate along with the threaded rod 221, across-shaped groove 212 is provided on the bottom surface of the base211 of the seat element 21. And, correspondingly, a cross-shaped wedge122 is provided on the bottom of the blind hole 11. As such, when thecross-shaped groove 212 and wedge 122 meet and lock to each other, theseat element is prevented from rotating along with threaded rod 221.

The weight element 23 can be made of a metallic material of a specificdensity such as steel, titanium, nickel, aluminum, copper, or eventhermoplastic polyurethane (TPU). Therefore a golfer can have multipleweight elements 23 at hand, each having a specific weight, so that onecan be picked and used depending on the golfer's requirement. Usually, agolfer bases on the point of fall and the trajectory of a previous hitto decide how the club head 1's center of gravity should be adjusted.Then, by replacing the weight elements 23 of the weight members 2 in theblind holes 11 as described above, the center of gravity of the clubhead 1 can be adjusted to fit more naturally to the golfer's specifichabit and stance. The club head 1 of the present invention can beintegrally formed without complex machinery process so that itsproduction process and cost can be effectively simplified and reduced.

As shown in FIG. 6, a club head 1A according to a second embodiment ofthe present invention has the blind holes 1A1 with longer depths thanthose of the previous embodiment. Inside the storage space 1A2 of eachblind hole 1A1, two opposing slots 1A23 and 1A24 are provided along theaxial direction and along the inner wall of the blind hole 1A1.Correspondingly, two radially protruding tenons 2A14 and 2A15 areprovided on the rim of the base 2A11 of the seat element 2A1. As such,the seat element 2A1 is prevented from rotation when the fasteningelement 2A2 is screwed. In the present embodiment, there are multiplefastening elements 2A2, each having a threaded rod 2A21 of a specificlength. When a particular fastening element 2A2 is used and screwed tojoin the seat element 2A1, the threaded rod 2A21 is able to run throughthe through channel 2A13 until its tip reaches the bottom of the blindhole 1A1. In the process, again, the slits 2A31 and 2A32 allows the twoends of the weight element 2A3 to expand and to press against the wallof the blind hole 1A1. However, due to the particular length of thethreaded rod 2A21, the weight member 2 is positioned at a particularlocation along the storage space 1A2 of the blind hole 1A1. As such, byusing different fastening elements 2A2, the center of gravity of theclub head 1A can be adjusted differently.

As shown in FIG. 7, a club head 1B according to a third embodiment ofthe present invention has the blind holes 1B1 with shorter depths thanthose of the first embodiment. In the present embodiment, the weightmember contains a fastening element 2′4 and a weight element 2′5. Thefastening element 2′4 is similar to those of the previous embodimentsand has a cone-shaped head and a threaded rob 2′41. On the other hand,the weight element 2′5 is like a basin having a front opening with slantinner wall for receiving the head of the fastening element 2′4. It alsocontains a number of slits 2′51 running axially from the front openingtowards the other end of the weight element 2′5. These slits 2′51 againallow the front opening to expand to press again the wall of the blindhole 1B1. Extending from the bottom of the weight element 2′5 is ahexagonal block 2′52 with an axial through channel 2′53 in the corner.The hexagonal block 2′52 is able to be fit inside a correspondingthrough hole 1B25 on the bottom of the hole 1B1. As such, when thefastening element 2′4 is screwed, the weight element 2′5 will not rotatealong with the threaded rod 2′41.

It will be understood that each of the elements described above, or twoor more together may also find a useful application in other types ofmethods differing from the type described above.

While certain novel features of this invention have been shown anddescribed are pointed out in the annexed claim, it is not intended to belimited to the details above, since it will be understood that variousomissions, modifications, substitutions and changes in the forms anddetails of the device illustrated and in its operation can be made bythose skilled in the art without departing in any way from the spirit ofthe present invention.

1. A club head comprising: a plurality of blind holes arranged atappropriate places other than the hitting surface of said club head, thebottom of each blind hole having a hole in the center; a plurality ofweight members removably housed inside said blind holes, respectively,each weight member having a tubular weight element, and a fasteningelement and a weight element plugged into a first end and a second endof said weight element, respectively; wherein said weight element has aplurality of first slits extending from said first end of said weightelement towards said second end and a plurality of second slitsextending from said second end towards said first end, said first andsecond slits being interleaved and uniformly spaced; said fasteningelement has a cone-shaped head and a threaded rod extending from thebottom of said head; said seat element has cone-shaped body with anaxial threaded through channel and a base having a slightly largerdiameter than that of said cone-shaped body; said weight element hascone-shaped inner walls at said first and second ends so as to fit theshapes of said head of said fastening element and said body of said seatelement; and said threaded rod has an appropriate length to be screwedor unscrewed through said weight element, said through channel of saidseat element, and into or from said hole on the bottom of each blindhole.
 2. The club head according to claim 1, wherein the bottom of eachblind hole has a cross-shaped wedge; and the bottom surface of said baseof said seat element has a correspondingly shaped groove so that, whensaid wedge is embedded into said groove as said threaded rod is screwedor unscrewed, said seat element is prevented form rotation.
 3. The clubhead according to claim 1, wherein said weight element is made out ofthe following material: steel, titanium, nickel, aluminum, copper, andthermoplastic polyurethane.
 4. A club head comprising: a plurality ofblind holes arranged at appropriate places other than the hittingsurface of said club head, the inner wall of each blind hole having aplurality of opposing axial slots; a plurality of weight membersremovably housed inside said blind holes, respectively, each weightmember having a tubular weight element, and a fastening element and aweight element plugged into a first end and a second end of said weightelement; wherein said weight element has a plurality of first slitsextending from said first end of said weight element towards said secondend and a plurality of second slits extending from said second endtowards said first end, said first and second slits being interleavedand uniformly spaced; said fastening element has a cone-shaped head anda threaded rod extending from the bottom of said head; said seat elementhas a cone-shaped body with an axial threaded through channel and a basehaving a slightly larger diameter than that of said cone-shaped body,said base having a plurality of tenons protruding radially from the rim;said tenons are fit inside said slots of said blind hole, respectively,so that, when said threaded rod is screwed or unscrewed, said seatelement is prevented from rotation; said weight element has cone-shapedinner walls at said first and second ends so as to fit the shapes ofsaid head of said fastening element and said body of said seat element;and said threaded rod has an appropriate length to be screwed orunscrewed through said weight element and said through channel of saidseal element until the tip of said threaded rod reaches the bottom ofsaid blind hole.
 5. The club head according to claim 4, wherein saidweight element is made one of the following material: steel, titanium,nickel, aluminum, copper, and thermoplastic polyurethane.
 6. A club headcomprising: a plurality of blind holes arranged at appropriate placesother than the hitting surface of said club head, the bottom of eachblind hole having a hole of a particular geometric shape in the center;a plurality of weight members removably housed inside said blind holes,respectively, each weight member having a weight element with abasin-like shape and a fastening element plugged into a front opening ofsaid weight element; wherein said weight element has a block extendingfrom the bottom of said weight element and having a correspondinggeometrical cross-sectional shape so as to fit inside said hole on thebottom of said blind hole; said weight element has a plurality of slitsextending from said front opening towards the bottom of said weightelement and a through channel through said block; said fastening elementhas a cone-shaped head and a threaded rod extending from the bottom ofsaid head; said weight element has a cone-shaped inner wall at saidfront opening so as to fit the shape of said head of said fasteningelement; and said threaded rod has an appropriate length to be screwedor unscrewed through and through channel of said weight element, andinto or from the interior of said club head.
 7. The club head accordingto claim 6, wherein said weight element is made one of the followingmaterial: steel, titanium, nickel, aluminum, copper, and thermoplasticpolyurethane.